I'm not 100% against randomized results, since it keeps things from being overly predictable... but in the case of things like this its just an example of how abusive the system can be.
This article actually does a fantastic job of summing up Luck in games: http://www.gamasutra.com/view/featur...uck.php?page=1
Going off the article, SE frequently employs Luck overtly and an incongruous manner (see the many superstitions and rumors from back in FFXI like having to face east on a earth day or that eating a specific food before planting in your house would alter the results.) Whether its a positive or negative application of luck is up for debate, though I feel its a negative one given the amount of investment demanded in this case, with the difficulty of reliably gathering high quality materials and being rewarded with a marginal increase in your 'luck'. (spending a week gets you a bonus 5% chance at your desired result while spending just an hour gets you the base chance or better)
I get the feeling it partly boils down to how over simple the crafting in this game is. Considering we have 8 entire classes dedicated to the act of crafting, you'd think there would be a more developed and interesting mechanic behind the act of crafting than "crafting text adventure".
Perhaps it may be fair to say SE is gimping potential rewards for crafting because its 'too easy a system'. This interacts poorly with the amount of investment and complexity of game play fighting has in the game.
I'm hoping the devs are open to considering redoing the crafting system on the same scale they revamped combat. Right now its all random chance, with the way orbs, abilities, and success interacts the only effort it requires of a player is the ability to use the arrow keys and the enter key. Our direct input is nothing but rolling dice with different weights.
Since SE is always looking for ways to slow down or stop RMT, think of it as an intelligence barrier to entry. Making crafting require more skill to do would cut out a lot of the bots and RMT who just mash macros all day in some forsaken corner of the world.